C-man,
We saw on Fall Creek in the Willamette system that after a couple years of dumping carcasses in the biologists told us that there was more everything from bugs to resident trout. It made a difference in that one little waterway.
We have stripped the forest covering, cut returning numbers to a fraction so there are no nutrients, and then, as Keith points out, we fish the bejeezus out of what's left.
While the differences of opinion about the effects of selective fishing and hatchery catch may persist, I think we all agree that habitat restoration is a no brainer.

PS The carcasses chop up better in the shredder if they are still frozen. What a mess.